" Gerastos granulosus, sometimes known as Proetus granulosus, is a small trilobite that lived during the Devonian right through to the Upper Permian. It is comes from the Middle Atlas Mountains of Morocco.The most distinctive trait of Gerastos is its bulbous glabella which is highly granulosed (hence the species name) and its short genal spines. Gerastos is one of the last lot of trilobites to go extinct in the Upper Permian. This particular specimen has not been painted although it has been repaired. The trilobite measures 1.0 inches long and 0.7 inches wide. The entire specimen measures 1.7 inches long, 1.9 inches wide and 1.3 inches high. The holochroal eye lenses are well-preserved and clearly visible. "
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